Gyroscope

Device for measuring or maintaining orientation

A gyroscope (from Ancient Greek γῦρος gŷros 'round' and σκοπέω skopéō 'to look') is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, due to the conservation of angular momentum.

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